The personal genomics company 23andme has added testing for the variants of the gene APOE; people who carry the ε4 variant of this gene have increased risk of developing sporadic Alzheimer’s disease, the most common version of the disease.
This is very tricky adventure for personal genomics. Smart Genetics was the pioneer in this field, but they closed down when they were found to be infringing upon the patent held by Duke University for APOE predictive testing for Alzheimer’s disease. The patent infringement case was ultimately technical, but it resulted in a spotlight being drawn to the issue of APOE testing for the masses, and some of the comments that were made at the time in a report by Nature News are relevant today.
“The test was never intended to be used for wholesale screening of non-cognitively impaired individuals,” said Alan Herosian, director of corporate alliances for Duke University.
Even more telling was the observation made by Allen Roses, the lead scientist on the Duke patent who said
“ethical aspects of risk assessments will change if clinical trials identify drugs to treat the disease. Currently, knowing one’s risk of developing the disease may simply cause needless worry, as there is no prevention or treatment.”
This is the heart of the issue, and has been discussed at length in the academic literature (here and there and here and there, for example). The debate goes something like this: finding out that one is at increased risk of developing Alzheimer’s disease may result in several things that are generally considered beneficial: people may alter their lifestyle (to reduce the likelihood of developing AD) or alter their plans for the future (enjoying life today rather than waiting) or even their purchase of long-term care insurance. There are also some potential problems, most notable among these that people may become distressed upon learning that there is an increase likelihood of AD in their future. It turns out that information can be harmful.
All of this is challenging enough in the context of a physician’s office – in the context of personal genomics, land mines abound.
To their credit, 23andme do not just offer the results outright, but rather lock them until the user reads an information sheet and acknowledges that they understand what the results do and do not mean. While people may click on the button to gain access to their information, it is another matter to conclude that they really understand the implications of learning their APOE status. (For a peek at the information sheet, you can follow the link from Dan MacArthur’s post on his results over at Wired).
Again, to give the company credit, they do provide ready access to genetic counsellors (at least in the United States), but only if users pursue that course of action, and the counselling is not free.
The major problem that 23andme’s program has is that it does not tell people that there is, at present, no effective treatment for Alzheimer’s disease. Moreover, despite all the wishful thinking out there, none of the lifestyle modifications that people adopt have been demonstrated to make a difference in outcome. It would seem to me that knowing such information would be relevant to people contemplating whether to push the “Show me my results” button, or even considering whether they might purchase the APOE test in the first place.
In this context, it is worth recalling the story of James Watson and the unveiling of his genome. Watson, who won the Nobel Prize for being a co-inventor of the structure of DNA, is arguably one of the most sophisticated consumers of genetic information on the planet. He was also one of the first people to have his genome scanned in the original Human Genome Project. Famously, the only gene in his personal genome whose status Watson elected not to learn about was APOE. One wonders if consumers of personal genomics products that include APOE would find that story to be helpful when contemplating what they may or may not want to know.
Hat tip to Alex Garnett for alerting me to 23andme’s new test.